|
|
Rogister Y., Le Moigne N., Hothem L., Mémin A., Hinderer J. (2010). Absolute gravity measurements at McMurdo Station, Scott Base and Mario Zucchelli Station in November 2009, SCAR meeting, Buenos Aires, Argentina, August 2010.
|
|
|
|
Hothem L., Le Moigne N., Rogister Y., Mémin A., Hinderer J. (2010). Absolute gravity measurements at McMurdo Station, Scott Base and Mario Zucchelli stations in November 2009, 2nd Symposium of the International Gravity Field Service, Fairbanks, Alaska, September 2010..
|
|
|
|
Amalvict M. et al. (2005). Absolute Gravity measurements in the Indian Ocean.
Abstract: Scientific Assembly of the International Associati
Programme: 337
|
|
|
|
Rogister Y., Hothem L. (2016). Absolute Gravity Measurements: Objectives, Results and Perpectives, POLENET Science Meeting, Columbus, Ohio.
|
|
|
|
Rogister Y, Hothem L, Bernard JD, Hinderer J, Wilson T, Capra A, Zanutta A, Winefield R, Collett D. (2012). Absolute Gravity Observations on Ross Island and in Terra Nova Bay in November-December 2011, SCAR Open Science Conference, Portland, Oregon, July 2012.
|
|
|
|
Plenier G., Camps P., Coe R.S. & Perrin M. (2003). Absolute palaeointensity of Oligocene (28-30 Ma) lava flows from the Kerguelen archipelago (southern Indian Ocean). Geophysical journal international, 154, 877–890.
|
|
|
|
Kreemer Corné, . (2009). Absolute plate motions constrained by shear wave splitting orientations with implications for hot spot motions and mantle flow
. J. Geophys. Res., 114(B10), B10405–.
Abstract: Here, I present a new absolute plate motion model of the Earth's surface, determined from the alignment of present-day surface motions with 474 published shear wave (i.e., SKS) splitting orientations. When limited to oceanic islands and cratons, splitting orientations are assumed to reflect anisotropy in the asthenosphere caused by the differential motion between lithosphere and mesosphere. The best fit model predicts a 0.2065°/Ma counterclockwise net rotation of the lithosphere as a whole, which revolves around a pole at 57.6°S and 63.2°E. This net rotation is particularly well constrained by data on cratons and/or in the Indo-Atlantic region. The average data misfit is 19° and 24° for oceanic and cratonic areas, respectively, but the normalized root-mean-square misfits are about equal at 5.4 and 5.2. Predicted plate motions are very consistent with recent hot spot track azimuths (<8° on many plates), except for the slowest moving plates (Antarctica, Africa, and Eurasia). The difference in hot spot propagation vectors and plate velocities describes the motion of hot spots (i.e., their underlying plumes). For most hot spots that move significantly, the motions are considerably smaller than and antiparallel to the absolute plate velocity. Only when the origin depth of the plume is considered can the hot spot motions be explained in terms of mantle flow. The results are largely consistent with independent evidence of subasthenospheric mantle flow and asthenospheric return flow near spreading ridges. The results suggest that, at least where hot spots are, the lithosphere is decoupled from the mesosphere, including in western North America.
Keywords: absolute plate motion, seismic anisotropy, mantle flow, hot spot, 8011 Kinematics of crustal and mantle deformation, 8158 Plate motions: present and recent, 8121 Dynamics: convection currents, and mantle plumes,
Programme: 133
|
|
|
|
Dellile D. (2004). Abundance and function of bacteria in the southern ocean. Cellular and molecular biology, 50, 543–551.
|
|
|
|
Kaarle J. Parikka, Stéphan Jacquet, Jonathan Colombet, Damien Guillaume, Marc Le Romancer. (2018). Abundance and observations of thermophilic microbial and viral communities in submarine and terrestrial hot fluid systems of the French Southern and Antarctic Lands (Vol. 41).
Abstract: Studies investigating viral ecology have mainly been conducted in temperate marine and freshwater habitats. Fewer reports are available on the often less accessible “extreme environments” such as hot springs. This study investigated prokaryotic- and virus-like particles (VLP) associated to hot springs, themselves situated in cold environments of the Southern Hemisphere (i.e. in the French Southern and Antarctic Lands). This was performed by examining their abundance in hot springs and surrounding temperate seawater using both epifluorescence microscopy (EFM) and flow cytometry (FCM), which was applied for the first time to such ecosystems. On one hand, prokaryotic abundances of 4.0 × 105–2.2 × 106 cell mL−1 and 7.0 × 104–2.8 × 106 cell mL−1 were measured using EFM and FCM, respectively. The abundances of virus-like particles (VLP), on the other hand, ranged between 9.8 × 105 and 7.5 × 106 particles mL−1 when using EFM, and between 1.3 × 105 and 6.2 × 106 particles mL−1 when FCM was applied. A positive correlation was found between VLP and prokaryotic abundances, while the virus-to-prokaryote ratio was generally low and ranged between 0.1 and 6. In parallel, samples and culture supernatants were also visualised using transmission electron microscopy. For this, enrichment cultures were prepared using environmental samples. Both raw sample and enrichment culture—supernatants were analysed for the presence of VLPs. Observations revealed the presence of Caudovirales, membrane vesicles and possibly a new type of virion morphology, associated to members of the order Thermotogales, a thermophilic and anaerobic bacterium.
Keywords: Abundance Epifluorescence microscopy Flow cytometry Hot spring Thermophilic Virus-like particle
Programme: 1077
|
|
|
|
David J. Yurkowski, Marie Auger‐Méthé, Mark L. Mallory, Sarah N. P. Wong, Grant Gilchrist, Andrew E. Derocher, Evan Richardson, Nicholas J. Lunn, Nigel E. Hussey, Marianne Marcoux, Ron R. Togunov, Aaron T. Fisk, Lois A. Harwood, Rune Dietz, Aqqalu Rosing‐Asvid, Erik W. Born, Anders Mosbech, Jérôme Fort, David Grémillet, Lisa Loseto, Pierre R. Richard, John Iacozza, Frankie Jean‐Gagnon, Tanya M. Brown, Kristin H. Westdal, Jack Orr, Bernard LeBlanc, Kevin J. Hedges, Margaret A. Treble, Steven T. Kessel, Paul J. Blanchfield, Shanti Davis, Mark Maftei, Nora Spencer, Laura McFarlane‐Tranquilla, William A. Montevecchi, Blake Bartzen, Lynne Dickson, Christine Anderson, Steven H. Ferguson. (2019). Abundance and species diversity hotspots of tracked marine predators across the North American Arctic (Vol. 25).
Abstract: Aim Climate change is altering marine ecosystems worldwide and is most pronounced in the Arctic. Economic development is increasing leading to more disturbances and pressures on Arctic wildlife. Identifying areas that support higher levels of predator abundance and biodiversity is important for the implementation of targeted conservation measures across the Arctic. Location Primarily Canadian Arctic marine waters but also parts of the United States, Greenland and Russia. Methods We compiled the largest data set of existing telemetry data for marine predators in the North American Arctic consisting of 1,283 individuals from 21 species. Data were arranged into four species groups: (a) cetaceans and pinnipeds, (b) polar bears Ursus maritimus (c) seabirds, and (d) fishes to address the following objectives: (a) to identify abundance hotspots for each species group in the summer–autumn and winter–spring; (b) to identify species diversity hotspots across all species groups and extent of overlap with exclusive economic zones; and (c) to perform a gap analysis that assesses amount of overlap between species diversity hotspots with existing protected areas. Results Abundance and species diversity hotpots during summer–autumn and winter–spring were identified in Baffin Bay, Davis Strait, Hudson Bay, Hudson Strait, Amundsen Gulf, and the Beaufort, Chukchi and Bering seas both within and across species groups. Abundance and species diversity hotpots occurred within the continental slope in summer–autumn and offshore in areas of moving pack ice in winter–spring. Gap analysis revealed that the current level of conservation protection that overlaps species diversity hotspots is low covering only 5% (77,498 km2) in summer–autumn and 7% (83,202 km2) in winter–spring. Main conclusions We identified several areas of potential importance for Arctic marine predators that could provide policymakers with a starting point for conservation measures given the multitude of threats facing the Arctic. These results are relevant to multilevel and multinational governance to protect this vulnerable ecosystem in our rapidly changing world.
Keywords: animal movement biologging climate change conservation fishes marine mammals protected areas seabirds
Programme: 388
|
|
